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Potato Solanum tuberosum is an economically significant crop with high nutritional value, which annually is adversely affected by fungal diseases, resulting in economic yield losses. In the present study, 25 fungal isolates with similar colony morphology and growth pattern were isolated from 30 potato tuber samples with symptoms of potato black scab (causal agent: Rhizoctonia solani) collected from the Sarab region, East Azarbaijan province. Identification of the fungal strains was carried out using a combination of morphological and molecular data from the ITS-rDNA region and the beta-tubulin gene (tub2). The inferred phylogenies based on the combined dataset of these two gene regions placed the examined strains together with sequence data of the type specimen of Trichocladium solani in the family Chaetomiaceae. The fungal strains cultured on oatmeal agar (OA) media produced simple, aseptate, acromonilioid conidiophores formed laterally on unbranched, transparent hyphae. The morphological characteristics of the examined strains were fully consistent with the description provided for the species T. solani. Pathogenicity assay on potato tubers under laboratory conditions confirmed T. solani isolates being pathogenic on potato. Trichocladium solani was recently described and reported as a new species causing yellow rot disease on potato tuber rot in Russia. In this study, T. solani is reported for the first time from Iran, and the morphological, pathological, and molecular characteristics of this species are determined. Geographical distribution, host range and economic impact of the the disease remain to be studied. [ABSTRACT FROM AUTHOR]

Rhynchosporium commune (formerly known as Rhynchosporium secalis), the causal agent of scald disease on barley, is known to spread asexually by splash dispersed conidia. However, there are multiple lines of evidence for the possibility of a clandestine sexual cycle occurrence in this species including extensive genotypic diversity, equal distribution of mating type alleles across the world and expression of mating type genes. In the current study, the potential for the occurrence of a sexual cycle amongst the Iranian population of R. commune was assessed by analyzing distribution and frequency of the mating type alleles at both micro and macro-spatial scales. A total of 95 single-conidial R. commune isolates were obtained from different barley fields in Kurdistan province. Previously designed primers were applied in a multiplex PCR assay to study distribution and frequency of the mating type alleles within and between populations. Totally, 67 isolates were determined as MAT1-1 and the remaining 28 isolates as MAT1-2 throughout the sampling counties. The results obtained at a macro-spatial scale revealed that unlike Kamyaran county (both MAT1-1 and MAT1-2 at an equal ratio), an unequal distribution of mating type genes was dominant among R. commune isolates in both Mariwan and Dehgolan counties. Our findings support a predominantly asexual reproduction for Mariwan and Dehgolan counties and the possibility of sexual stage occurrence in Kamyarna county.

In the present study, the antagonistic capability of bacterial agents inhabiting the rhizosphere of sugarbeet plants were evaluated against Cercospora beticola Sacc. under laboratory and greenhouse conditions. After preliminary screening using the dual culture method, 14 strains with higher antagonistic capability were selected for further inhibitory assays against C. beticola. Bacterial strains were identified based on the sequence data of the small subunit-rDNA (SSU-rDNA) gene. Based on the SSU sequence data, the identity of bacterial strains were determined as Bacillus (10 strains: RB1, RB2, RB3, RB4, RB5, RB6, RB7, RB8, RB9, RB10), Paenibacillus (two strains: RP1, RP2), Enterobacter (one strain: RE), and Pseudomonas (one strain: RPs). The results obtained in this study showed that in all of the assays (dual culture, volatile and non-volatile metabolites) bacterial antagonists significantly inhibited the growth of C. beticola compared to the control. Bacillus (RB2) showed the highest inhibition rate on C. beticola in all of the assays. Based on the results of the laboratory assays, three bacterial strains RB2 (Bacillus), RPs (Pseudomonas), and RE (Paenibacillus) were selected for greenhouse assays. The experiment was designed based on a completely randomised design (CRD) with the application of antagonists prior to, simultaneously, and after inoculation with C. beticola on sugarbeet leaves. The reduction in disease severity was evaluated seven days after inoculation. The results of greenhouse assays were consistent with the results of laboratory studies. The obtained results showed that bacterial antagonists significantly reduced the disease severity when compared to the control.

We report the first case of chafer beetle [Anisoplia austriaca (Herbst 1783)] mortality caused by Actinomucor elegans var. elegans in wheat fields of the Kurdistan province, Iran. For three years, dead larvae of Anisoplia austriaca were collected from wheat fields of the Kurdistan province. Similar isolates of a fast-growing fungus were recovered from all samples. The fungal isolates were identified as A. elegans var. elegans based on morphological and cultural characteristics. The identity of the species was further confirmed using sequence data of the ITS (Internal Transcribed Spacer) region of ribosomal DNA. Koch’s postulates were fulfilled by the inoculation of the larvae of A. austriaca and Galleria mellonella (Linnaeus, 1758) (as the model insect) using the spore suspension of A. elegans var. elegans. The viability of sporangiospores was evaluated using a spore dilution technique on germination medium. The results on the pathogenicity (100% mortality in A. austriaca larvae) and viability tests (germination: 95.45%) demonstrated that A. elegans var. elegans can be considered as a potential biocontrol agent against the chafer beetle. Field experiments are still required to evaluate the capacity of A. elegans as a biological control agent.

Trunk disease is a major problem on grapevine in Zanjan province, causing serious decline, despite which its aetiology remains unknown. The purpose of this study was to investigate factors involved in grapevine decline in vineyards of Zanjan province. Samples were collected from twigs and branches of grapevines in the region between October and November 2018. Fungal isolates were identified based on morphological characteristics and ITS‐rDNA sequence data for selected isolates. The frequency and diversity of the fungal community recovered from grapevines in Darreh Sejin in Zanjan province were higher than in other regions. A total of 112 fungal isolates comprising 22 species were recovered. Phaeoacremonium minimum, Microsphaeropsis olivacea and Kalmusia variispora were identified as the dominant species in the region examined and could be considered the main trunk pathogens of grapevines in Zanjan region. In inoculation tests, M. olivacea was proved to be pathogenic on grapevine for the first time in this study. [ABSTRACT FROM AUTHOR]

The genus Cercospora contains many devastating plant pathogens linked to leaf spot diseases afflicting various plants. Identification of Cercospora species based on morphology or host plant association has proven unreliable due to simple morphology and wide host range in many cases; hence, multi-gene DNA sequence data are essential for accurate species identification. Considering the complexity and cost involved in application of multi-locus DNA phylogenetic approaches for species delineation in Cercospora; rapid and cost-effective methods are urgently needed for species recognition. In this study, we applied rep-PCR (repetitive-sequence based polymerase chain reaction) fingerprinting methods referred to as BOX-PCR to differentiate species of Cercospora. Cluster analysis of the banding patterns of 52 Cercospora strains indicated the ability of BOX-PCR technique using BOXA1R primer to generate species-specific DNA fingerprints from all the tested strains. Since this technique was able to discriminate between all the 20 examined Cercospora species during this study, which corresponded well to the species identified based on multi-gene DNA sequence data, our findings revealed the efficiency of BOX-PCR system as a suitable complementary method for molecular identification of the genus Cercospora at species level. [ABSTRACT FROM AUTHOR]

Leaf stripe disease caused by Pyrenophora graminea is an economically significant disease of cultivated barley worldwide, including Iran. Considering economic impact of this disease on barley industry in Iran, in this study genetic diversity of P. graminea populations mainly collected from barley (229 isolates) in different regions of East Azerbaijan Province was examined using ISSR and RAPD molecular markers. The average polymorphic information content (PIC) values for ISSR and RAPD were 0.28 in both markers, and a significant correlation was observed between ISSR and RAPD data (r =.78, p <.05). No clear clustering was found within P. graminea populations in relation to their geographical origins. Applying the unweighted pair group method with arithmetic mean (UPGMA) procedure and principal coordinates analysis (PCoA) revealed no obvious clustering of isolates based on geographic region. Totally, gene diversity of 0.2 was noticed among P. graminea isolates. High level of genetic differentiation (PhiPT = 0.257; p ≤.001), with 74% of the genetic variation occurring within populations and 26% occurring among populations, indicated the existence of population differentiation. In addition, a moderate amount of gene flow (Nm = 1.1985) was found between populations. Information obtained from this study may be beneficial to design and improve management strategies such as breeding resistant barley varieties to leaf stripe disease. [ABSTRACT FROM AUTHOR]

In this study, PLANT TONIC9 (EOX-SOV) was screened for its in vitro efficacy against some fungal species. PLANT TONIC9 significantly inhibited the mycelial growth and conidial germination of all tested species as compared with untreated control. The highest mycelial growth and conidial germination inhibition percentage was recorded for Monilinia species while the lowest inhibition percentage was recorded for Rosellinia sp. The lowest minimum inhibitory concentration (MIC) value was observed against Monilinia fructigena and Monilinia fructicola followed by Monilinia laxa and Botrytis cinerea. Also the in vivo efficacy of PLANT TONIC9 against M. laxa was investigated. Application of PLANT TONIC9 significantly reduced the severity and incidence of brown rot disease on apple as compared with the control. PLANT TONIC9 treatments were also successful to retain the size, specific gravity, and shelf life of tested fruits and to decrease their spoilage percentage over the experimental period as compared with the control. [ABSTRACT FROM AUTHOR]

Pyrenophora teres is an economically important pathogen of barley worldwide causing net blotch diseases. In this study, the frequency and mating‐type alleles's distribution as well as genetic diversity of P. teres were assessed on micro‐spatial scale and also on macro‐geographical scale to find out whether a sexual cycle is possible within its Iranian populations. A multiplex PCR assay was developed for simultaneous identification and recognition of P. teres f. teres and P. teres f. maculata and to screen their mating‐type alleles. 118 isolates of P. teres were procured from barley fields of East Azerbaijan province during 2017–2018. Among 89 isolates of P. teres f. teres examined, 39 isolates were found as MAT1‐1 and 50 isolates were found to be MAT1‐2. Among 29 isolates of P. teres f. maculata examined, 17 isolates were found as MAT1‐1 and 12 isolates were found to be MAT1‐2 with the dominancy belonging to MAT1‐1. Nearly same mating‐type alleles distribution within and between various populations of P. teres f. teres (1:1 ratio; χ2 = 1.36) and P. teres f. maculata (1:1 ratio; χ2 = 0.862) was observed. Genetic diversity assessment of 118 P. teres isolates was carried out through inter‐simple sequence repeat (ISSR) analysis and results revealed that there was 70.83% and 63.89% polymorphism among the isolates of P. teres f. teres and P. teres f. maculata, respectively. No relation was observed between the isolates and their mating as well as geographical type. Among collected isolates (89 P. teres f. teres and 29 P. teres f. maculata isolates), the gene diversity was generally similar (h = 0.280 and h = 0.238 for P. teres f. teres and P. teres f. maculata, respectively). Based on our findings and referring to the prior data on the structure of P. teres population, we conclude that in the majority of tested areas, this fungal species might have the potential to undergo regular sexual recombination cycles. [ABSTRACT FROM AUTHOR]

Fusarium species can have different lifestyles, including those of endophytes, parasites, or pathogens of plants, as well as pathogens or mutualists of animals. Fungicolous Fusarium species have been also reported in some studies, however, the information on the Fusarium interactions with other fungi is still unclear and the diversity of fungicolous Fusarium species is poorly known. In this study, we provide a survey of fungicolous Fusarium species and their hosts, and instructions for their isolation and identification. According to the survey, 80 fungicolous Fusarium isolates were reported associated with 36 host species and 32 fungal genera. The fungicolous isolates belong to 24 species grouped in nine species complexes (SC)—Fusarium chlamydosporum SC, Fusarium fujikuroi SC, F. heterosporum SC, F. lateritium SC, F. oxysporum SC, F. incarnatum-equiseti SC, F. sambucinum SC, F. solani SC (=Neocosmospora genus), and F. tricinctum SC. Fusarium associations with other fungi were predominantly necrotrophic. The prevalent fungal hosts for fungicolous Fusarium isolates were members of the sub-kingdom Dikarya, mostly microfungi. Other hosts belong to the sub-kingdom Mucoromyceta of the kingdom Fungi and to the phylum Oomycota (fungal-like organisms) of kingdom Straminipila. With this review, we hope to highlight the fungicolous associations of Fusarium, and to expand the understanding of the ecology and diversity of these fungi. [ABSTRACT FROM AUTHOR]

Pomegranate (Punica granatum) is native to Iran and neighbouring countries and is negatively affected by a wide range of diseases. Canker and dieback diseases caused by Cytospora punicae and members of the family Botryosphaeriaceae are the main trunk diseases on pomegranate. In summer 2017, progressive dieback of branches on some young pomegranate trees was observed in orchards of the Gorgan Region (Golestan province, Northeast Iran). Fungal colonies with similar colony colour were isolated from symptomatic tissues. The identity of the causal agent was determined as Neofusicoccum parvum, based on a polyphasic taxonomic approach including morphological features of conidiomata and phylogenetic inference based on the ITS‐rDNA region and translation elongation factor 1 alpha (tef1‐α) gene. Koch's postulates were fulfilled using an excised shoot method. This study provides the first report on the occurrence of N. parvum as a cause of branch canker on pomegranate in Iran. [ABSTRACT FROM AUTHOR]

• Two tetrasubstituted α -pyrones were identified from the endophytic fungus Neurospora udagawae • Udagawanone B constitutes a rare example of a C-4 O -demethylated α -pyrone. • Their antimicrobial and cytotoxic activities are reported. Two new α -pyrone derivatives, udagawanones A (1) and B (2), along with the known compounds (Z)-4-hydroxy-3-(3-hydroxy-3-methylbut-1-en-1-yl)benzoic acid (3), isosclerone (4), cyclo -(L -Leu- L -Pro) (5), and cyclo -(L -Pro- L -Tyr) (6), were isolated from cultures of the endophyte Neurospora udagawae. Their structures were elucidated by extensive spectroscopic methods and single crystal X-ray diffraction. Both compounds feature oxidized functionalities at the C-2 position not previously observed in other tetrasubstituted α -pyrones from fungi. Compound 1 exhibited moderate antibacterial (vs. Staphylococcus aureus) and antifungal (vs. Rhodoturula glutinis) activities and cytotoxicity against KB3.1 cells. [ABSTRACT FROM AUTHOR]

Strawberry anthracnose caused by Colletotrichum spp. is considered one of the most serious and destructive disease of strawberry worldwide. Weeds, as possible hosts of the pathogen, could have a role as potential inoculum reservoir. To prove this hypothesis, symptomless weeds were collected in strawberry fields showing anthracnose symptoms in Iran. Ten isolates with Colletotrichum -like colonies were recovered from symptomless Amaranthus viridis L., Convolvulus arvensis L., Fumaria officinalis L., Lactuca serriola L., and Sonchus oleraceus L. plants. The isolates were identified as C. nymphaeae , based on a combination of morphological and sequence data of TUB and GADPH genes. This identification was further validated using Rep-PCR fingerprinting analysis, which produces species-specific DNA fingerprints and unveils inter and intra variation of the species examined in this study. Moreover, rep-PCR marker was used to reveal accurate taxonomic position of Colletorichum spp. causing strawberry anthracnose belonging to the C. acutatum complex, including C. acutatum sensu stricto, C. fiorinae, C. godetiae, C. nymphaeae, C. salicis , and C. simmondsii. The C. nymphaeae isolates originating from symptomless weeds confirmed their pathogenicity on detached strawberry, proving that weeds in strawberry field may have a role as reservoir of inoculum. However, further studies are necessary to quantify their actual contribution to anthracnose epidemics in strawberry fields. [ABSTRACT FROM AUTHOR]

Two new metabolites possessing the unusual 1-oxa-7-azaspiro[4.4]non-2- ene-4,6-dione core ( 2 , 3 ) along with the recently described pseurotin A 3 ( 1 ) were isolated from the pathogenic fungus Wilsonomyces carpophilus ( previously named Stigmina carpophila ). The producer organism was obtained from Prunus armeniaca collected in Iran and was identified by morphological and molecular phylogenetic methods. The structures of the isolated compounds were elucidated on the basis of extensive NMR spectroscopic analysis, high-resolution mass spectrometry and ECD analysis. The compounds were screened for their antimicrobial, cytotoxic, nematicidal and biofilm inhibition activities but, no significant effect was observed. To the best of our knowledge, this is the first report on the isolation of secondary metabolites produced by W. carpophilus . [ABSTRACT FROM AUTHOR]

Trunk diseases are potential threats to the poplar industry worldwide, including Iran. A survey on trunk diseases of Populus nigra in north-western Iran revealed a new canker disease associated with dieback and decline of this host in West Azarbaijan Province of Iran. Wood samples were collected from poplar trees showing canker, dieback and decline symptoms and taken to the laboratory. A total of 173 fungal isolates were recovered from symptomatic tissues, of those 147 isolates had similar cultural and morphological features on potato dextrose agar. Based on a combination of morphological characteristics and phylogenetic inferences including DNA sequence data from the internal transcribed spacer regions ( ITS1, 5.8S rDNA, and ITS2), all 147 isolates were identified as Cryptosphaeria pullmanensis. The remaining 26 isolates were identified as Cytospora chrysosperma. Pathogenicity of Cr. pullmanensis on two-year-old P. nigra and Populus alba saplings under glasshouse conditions confirmed that Cr. pullmanensis is pathogenic on P. nigra and P. alba. Cryptosphaeria pullmanensis is here reported from Iran causing Cryptosphaeria canker on poplar trees for the first time. However, its host range, the extent of geographical distribution and management strategies remain to be examined. [ABSTRACT FROM AUTHOR]

Strawberry anthracnose, caused byColletotrichum nymphaeae,is mainly controlled by the application of synthetic chemical fungicides. The present study assessed the antimicrobial activity of essential oils (EOs) from dill (Anethum graveolensL.) seed againstC. nymphaeae.The antifungal effects of dill seed EO onC. nymphaeaewas initially evaluatedin vitroand further extended asin vivocondition. The results indicate that in the contact and volatile assays, dill seed EO significantly inhibited mycelial growth ofC. nymphaeaeat all concentrations tested. Conidia germination was also significantly inhibited at concentrations of 250 – 1000 ppm. Disease incidence and severity of anthracnose on strawberry fruits were significantly reduced compared with infected control, from concentrations of 500 and 50 ppm, respectively. The results confirm the efficacy of dill seed EO againstC. nymphaeae,which may represent an alternative to synthetic chemical fungicides to control strawberry anthracnose pre- and post-harvest. [ABSTRACT FROM PUBLISHER]

Polygonatum odoratum (Mill.) Druce (Angular Solomon's seal) is a well-known ornamental plant and herbal drug, which is used in traditional medicine. Severe leaf spots were observed in wild Angular Solomon's seal plants in a public park in Trento, Italy. A combination of morphological and molecular characteristics, including sequence data of ITS- rDNA, large subunit ( LSU), beta tubulin ( TUB) and glyceraldehyde 3-phosphate dehydrogenase ( GAPDH) led to identification of two species, namely Phoma odoratissimi and Colletotrichum dematium s. str., isolated from these leaf spots. Pathogenicity of the isolates was confirmed on wounded leaves of Po. odoratum; indeed, both species induced leaf spot symptoms on inoculated leaves within 10 days of inoculation. This is the first report of leaf spot disease caused by Ph. odoratissimi and C. dematium s. str. on Po. odoratum, which can be considered a new host for both the species examined in this study. In addition, isolation of Ph. odoratissimi represents a new record for the mycobiota of Italy. [ABSTRACT FROM AUTHOR]

Trunk diseases are potential threats for almond productivity and longevity worldwide, including Iran. In a recent survey on fungal species associated with trunk diseases of almonds in north-western Iran, Collophora isolates (tentatively identified as Collophora hispanica) were recovered with high frequency from wood samples with internal necrosis and brown to black vascular streaking of almond trees showing symptoms of decline. However, the pathogenic potential of Collophora isolates on almond trees in Iran remains unproven. In this study, the identity of the isolates was further confirmed as C. hispanica based on a combination of morphological data and sequence data of ITS- rDNA region, and pathogenicity of C. hispanica isolates on almond was evaluated using excised shoot method and in greenhouse experiments . Collophora hispanica isolates induced lesions statistically different from the control, in both excised shoot method and greenhouse assays. Significant differences were observed among the isolates in the length of the lesion induced on wood. Collophora hispanica should be considered as the main trunk pathogens of almond trees in north-western region of Iran. The distribution and host range of this new pathogen on almond remains to be studied. [ABSTRACT FROM AUTHOR]

Togninia minima is the main fungal species associated with grapevine leaf stripe disease worldwide. This species is mainly known from its asexual state in nature; nevertheless, a biallelic heterothallic mating strategy has been confirmed for this species based on in vitro crossing studies. There are no data available on the incidence of an active sexual cycle within the populations of this species in many grapevine-producing countries as well as Iran. The possibility of a clandestine sexual cycle within the Iranian isolates of T. minima was evaluated by analysing the distribution and frequency of the mating-type alleles on a microspatial and a macrogeographical scales. Towards this aim, a total of 90 T. minima isolates were recovered from grapevines with esca disease from the vineyards in north and north-western Iran. A multiplex PCR method previously designed by authors was applied for simultaneous identification and determination of the mating-type alleles in T. minima populations. The results on the screening of mating-type alleles using multiplex PCR method revealed the mating-type identity of 77 isolates as Mat1-2 and 23 isolates as Mat1-1. Our results showed that both Mat1-1 and Mat1-2 isolates are present in a single vineyard and even on single vines. The distribution of mating-type alleles in the sampled area skewed from the 1 : 1 ratio (77 : 23); however, co-occurrence of both mating types in a single vineyard and even on single vines is suggestive for the presence of an active sexual cycle for T. minima in north-western Iran. [ABSTRACT FROM AUTHOR]

Bacillus thuringiensisvar.kurstaki(Berliner) (Bt) has been suggested as a biological control agent forTuta absoluta(Meyrick). The objective of this study was to determine the interaction between abamectin, azadirachtin, indoxacarb, chlorantraniliprole, dichlorvos and metaflumizone with Bt. Effect of recommended doses of the chemical insecticides on colonisation of Bt was also investigated in culture medium. Except for metaflumizone, none of the chemicals tested reduced the colonisation of Bt compared with control. Interaction between Bt and the chemical insecticides on 2nd-instar larvae was also assessed. In interaction tests, Bt was applied at LC50level, 0, 12, 24 or 36 h after treating the larvae with LC10or LC25of the chemical insecticides. An antagonistic effect was observed in all treatments where Bt was applied immediately after the chemical insecticide. Also, antagonism was observed when treatment with Bt was done 12 h after azadirachtin and metaflumizone applications. Applying Bt 12 and 24 h after treatment with LC25of chlorantraniliprole, dichlorvos and abamectin resulted in synergism. But, synergism with LC10of dichlorvos and abamectin was observed only after 12 h. Additive effect was observed in the rest of the time and concentration combinations. Based on the results obtained, simultaneous use of the chemical insecticides tested and Bt is not recommended forT. absolutacontrol; and an appropriate time interval should be taken into consideration accordingly. [ABSTRACT FROM PUBLISHER]

A new species of Brachytydeus Thor, 1931 (senior synonym of Lorryia Oudemans, 1925 sensu Kaźmierski), Brachytydeus persiaensis n. sp., is described and illustrated. It was collected from peach orchards soil in Shendabad, East Azerbaijan Province, Iran. [ABSTRACT FROM AUTHOR]

The genusPythium, with slightly over 140 described species, has been classified traditionally with other filamentous, coenocytic, sporangia-producing fungi as “Phycomycetes”. However, with recent advances in chemical, ultrastructural and molecular studies,Pythiumspp. are now considered as “fungus-like organisms” or “pseudo-fungi” and are placed in the kingdom Chromista or kingdom Stramenopila, distinct from the true fungi or the kingdom Fungi. There is no comprehensive web-based identification key available for the identification of all describedPythiumspecies. This article describes a web-based identification tool (which has been described by the authors under the name of Fungid) that uses morphological features. For the isolate in question, the software compares the unknown isolate with near to 90 known species submitted in the database. One or more than one species is suggested to the user by the software. [ABSTRACT FROM PUBLISHER]